681139783 has 4 divisors (see below), whose sum is σ = 681387840. Its totient is φ = 680891728.

The previous prime is 681139769. The next prime is 681139793. The reversal of 681139783 is 387931186.

681139783 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 681139783 - 2²⁹ = 144268871 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681139703) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 119863 + ... + 125416.

It is an arithmetic number, because the mean of its divisors is an integer number (170346960).

Almost surely, 2^681139783 is an apocalyptic number.

681139783 is a deficient number, since it is larger than the sum of its proper divisors (248057).

681139783 is a wasteful number, since it uses less digits than its factorization.

681139783 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 248056.

The product of its digits is 217728, while the sum is 46.

The square root of 681139783 is about 26098.6548120780. The cubic root of 681139783 is about 879.8569770146.

The spelling of 681139783 in words is "six hundred eighty-one million, one hundred thirty-nine thousand, seven hundred eighty-three".